Wireless local area networks (LANs), typified by IEEE (Institute of Electrical and Electronics Engineers) 802.11, have in recent years been widespread, leading to an increase in the number of wireless LAN-capable products.
Technologies for performing efficient communication between a plurality of communication apparatuses have been developed to respond to a trend. A multicast scheme in which frames are transmitted to one or a plurality of communication apparatuses at one time is one of the technologies.
Here, it may be desirable to give a delivery acknowledgment (which will also be referred to as an acknowledgment (ACK) below) with respect to multicast frames, like unicast frames, in view of a reinforcement of reliability of communication. A block ACK (BA), which is a delivery acknowledgment with respect to a plurality of frames, is such a delivery acknowledgment.
For example, Patent Literature 1 discloses an invention relating to a wireless communication apparatus which performs transmission of a block ACK request (BAR) frame indicating a request for transmission of a BA frame and reception of a BA frame that is a response to the BAR frame for each terminal in chronological order after transmitting multicast frames to each of the terminals.